Caenispirillum deserti sp. nov., a spheroplastforming bacterium isolated from a salt desert

Abstract

A Gram-stain-negative, vibrio-shaped, spheroplast-forming, motile, aerobic bacterium was isolated from the soil of a salt desert in Kutch, Gujarat, India. The strain, designated JC232T, was oxidase- and catalase-positive. 16S rRNA gene sequence analysis indicated that strain JC232T was a member of the genus Caenispirillum and was related most closely toCaenispirillum salinarum AK4T (98.9% similarity) and Caenispirillum bisanense K92T (96.8%). Genome relatedness based on DNA–DNA hybridization of strain JC232T with the type strains of closely related species was less than 40%. The DNA G+C content of strain JC232T was 70mol%. Phosphatidylglycerol, phosphatidylethanolamine, phosphotidylcholine, diphosphatidylglycerol, two unidentified amino lipids (AL1 and 2) and four unidentified lipids (UL1–4) were the polar lipids of strain JC232T. C18:1ω7c/C18:1ω6c, C16:0 and C16:1ω7c/C16:1ω6c were the major ( > 15%) fatty acids of strain JC232T, with minor amounts of C12:0, C14:0 3-OH/iso-C16:0 I, C18:1 2-OH, C18:0, C16:0 3-OH and C19:0cycloω8c. Although strain JC232T shared the predominant ubiquinone system (Q10) with the type strains of C. salinarum and C. bisanense, it differed from the latter in polar lipid profile, NaCl growth range and other phenotypic/physiological properties. On the basis of morphologi-cal, physiological, genotypic, phylogenetic and chemotaxonomic analyses, strain JC232T is considered to represent a novel species of the genus Caenispirillum, for which the name Caenispirillum deserti sp. nov. is proposed. The type strain is JC232T (=KCTC 42064T=NBRC 110150T).